Dietary fructose is an important nutrient and major source of energy in the American diet. However, recent evidence suggests that dietary fructose may adversely affect fasting serum total and LDL cholesterol levels. If this is true, replacement of fructose and fructose-containing disaccharides like sucrose in the American diet with glucose could have significant public health benefits. The present study proposes to assess the effects of dietary fructose on serum lipids.